Electrical distribution system



March 27, 1945.v

W. H. FRANK I'L ELECTRICAL DISTRIBUTION SYSTEM Filed July 18, 1942-Patented Mar. 27, 1945 ELECTRICAL DISTRIBUTION SYSTEM William H. Frank,Robert L. Frank, and Lawrence E. Fisher, Detroit, Mich.

Application July 18, 1942, Serial No. 451,412

1 Claim.

This application relates to electrical distribution systems.

In a prior Patent No. 2,287,502 of June 23, 1942, particularly Figs.1-3, and in a prior application Serial No. 421,378 filed December 2,1941, now Patent No. 2,343,216 of February 29, 1944, there are disclosedvarious arrangements for supporting and maintaining in assembly theconductors oi.' an electrical distribution system. The system hereof isgenerally similar to the above mentioned systems and this applicationdiscloses a diierent and supporting arrangement than those of theapplications just mentioned, preserving, however, the relativearrangements and spacings of the conductors and casing, as set forth inthe descriptions of the above mentioned systems.

In the Patent No. 2,287,502 the conductor supporting and spacingarrangements include pedestal type insulators 50, cross pieces 50A andbolts 52. Insulation 23--24 separates conductors of opposite polarity.

In Patent No. 2,343,216 cross bars 20-23, E type insulator blocks 2|,and spring hooks 24 are utilized and no solid insulation is employedbetween the conductors of opposite polarity comparable to the insulation23-24 oi Patent 2,287,502.

In this application a different construction is provided and the samewill now be described upon reference to the appended drawing.

In this drawing,

Fig. 1 is a transverse section view.

Fig. 2 is a detailed section on line 2-2 of Fig. 1.

Fig. 3 is a detailed view of the arrangement for securing lapping endsof conductors.

Fig. 4 is a section on line 4-4 of Fig. 3.

Fig. 5 shows a bus bar connection arrangement.

In a system of the character described, unit lengths of encased bus barsare joined end to end to form a run of encased bus bars. The casing oi'each unit length is longitudinally split to provide casing halves I0having flanges II joined by bolts I2. The casing length contains lengthsI4 of thin wide iiat bus bars or conductors each of which is wrappedwith insulation tape I5. A solid insulation sheet I6 separates the busbars which are arranged in pairs. The two conductors of each pair are ofdiierent phases and the six conductors shown are arranged for threephase distribution and each phase includes a conductor of two diierentpairs. In the arrangement shown in Fig. 1, the conductors may beconsidered as of three phases ABC with the arrangement such as that ofFig. 5 which shows an arrangement ABC CAB with tie straps 29 used toconnect bus bars AA, BB, and CC.

For tightly securing the lapping portions oi the bus bars spring steelwashers Il, splined nuts Il and bolts I9 are employed, as shown in Figs.3 and 4.

At longitudinally spaced points, there are disposed metal channels orcross bars 20 arranged in two sets; one set may be welded to the lowercasing half I0 and is preferably so arranged; the other set is againstbut not secured directly to the upper casing half I0. Disposed withinthe cross bars 20 are insulating blocks 2| having notches or grooves '22formed for receiving the edges of the bus bars. Washers 23 and theinsulation I 6 which spaces the bus bars of a pair relatively, serve tospace the upper row of blocks 2l from the lower row. Bolts 24 threadedinto nuts 25 pass through openings in the insulation I6, the washers 23,the blocks 2|, and the cross bars 20 to hold the blocks, the cross barsand insulation in a tight and firm unitary assembly. The heads of thebolts and the nuts 25 are received Within dimpled embossments 2S seatingin complementary dimples of the blocks 2 I, which help relatively locatethe parts 2 I-20 during assembly.

'Ihe arrangement herein disclosed suitably maintains the conductors inplace Without piercing or damaging the bus bars or the insulationcovering or tape I5 wrapped around them, and adequately restrainsshifting of the conductors whether the bus bars are installed in a runwith the axis of the bolts 24 horizontal or vertical.

The entire assembly of all the parts shown except the casing halves andtheir bolts I 2 may be made outside of the casing halves and thendisposed within casing halves; or else a conductor run may be installed,after which the casing halves may be mounted around the installed busbar run. However, neither of the foregoing assembly procedures andinsulation procedures is as desirable as a procedure wherein cross bars20 are welded to one of the casing halves and then the bus bars andblocks and the other cross bars 20 and the bolts 24 are assembled withrespect to that lower casing half and after which the upper casing halfis applied, to form a complete unit length or section of bus way to beinstalled in a run by being Joined end to end with other unit lengths.

The inter-pair spacing is clearly shown to be considerably greater thanthe intra-pair spacing of the conductors and the blocks 2| and the bolts24 are disposed within the large inter-pair spaces.

The cross bars 20 and the bolts 24 form iron loops around the pairs ofconductors and while this is ordinarily considered objectionable inalternating current distribution systems, it is found not to beobjectionable here because or the arrangement oi' pairs and phases ofthe conductors.

Further the blocks and the bolts are dimensioned the same regardless ofthe width of the conductors. It, is present practice to make theconductors of varying width for varying capacities of distributionsystems; by using our arrangements, the same blocks 2l and bolts 24 maybe utilized regardless of the varying width of the conductors. Only thewidths of the conductors themselves, the widths of the-casing halves.and the lengths of the cross bar 20 will vary.

Variations in sizes may be obtained very simply, because the arrangementvherein disclosed does not depend upon standardized conductor width somuch as it depends upon standardization of the thickness of theconductors, the spacing between the conductors, and also between theconductors and the casing, and the depth of the easing. These standardsare very easy to maintain and the arrangement herein shown may beutilized for varying sizes of bus way systems without changing the sizesor dimensions of the blocks 2| or the bolts 24.

In addition, the arrangement herein disclosed is such that there is norequirement for perforating the casing in order to mount the conductorsor other parts in place and to hold them securely.

Excessive perforation in casings of distribution systems isconsideredundesirable. No such perforation is required in the system herein shown.

In addition, excessive manipulation of the heavy and large casingsections for mounting the conductors therein is eliminated here becauseof the arrangement disclosed.

An assembly bench of the character shown in Patent No. 2,343,216 may beemployed. A casing section I0 may be laid on that bench and the crossmembers 20, if not already welded thereto, may be welded to it at thattime; bolts 24 will be passed through the cross bars 20 before they arewelded to the lower casing section. Then the blocks and the conductorsand the insulation are built up over the lower cross bars and bolts,after which the nuts 25 are threaded onto the upper or free ends of thebolts 28, then the upper casing section I0 may be laid over the assemblyand bolted to the fitted lower casing section I0 already on the bench. Y

4Now having described the system herein disclosed, reference should behad to the claim which follows:

We claim:

In a polyphase electrical distribution system, a plurality of laterallyspaced pairs, each pair comprising transversely spaced elongatedconductors, the inter-pair spacing being greater than the intra-pairspacing, with each phase including two conductors of diierent pairs andwith each pair including two conductors of diierent phases, and meansfor tying together the said conductors into a unitary assemblycomprising transverse cross bars, and bolts in the inter-pair spacingconnecting the cross bars and drawing them towards each other forretaining the conductors in assembly, and means for maintaining theintra-pair spacing, and insulating blocks between the cross bars forrestraining the shifting of the conductors laterally, thus maintainingtheir inter-pair spacings, the cross bars and the bolts being of ferrousmetal and forming metal loops around the pairs of conductors.

' WILLIAM H. FRANK.

ROBERT L. FRANK. LAWRENCE E. FISHER.

